Use of glass compositions for achieving an antioxidative effect

ABSTRACT

The invention relates to the use of glass compositions in the form of glass powders, glass ceramics, fibers, granules, and spheres for achieving an antioxidative effect. With it, the glass composition may be used in a versatile manner, such as in cosmetic products, medical products, edibles, paints and lacquers, plasters, cements and concrete, in antifouling products and in polymers. Because of the high photo and temperature stability the antioxidants of the present invention are superior to the organic substances known so far. In addition the glass compositions in contact with human being are non-irritant to skin and even edible, furthermore toxicologically harmless and environmentally compatible.

FIELD OF THE INVENTION

The invention relates to the use of glass compositions in the form of glass powders, fibers, granules, and spheres for achieving an antioxidative effect.

The glass compositions according to the present invention may also be transformed into glass ceramics having a different degree of crystallinity by an annealing step and can be used as antioxidants. Also a complete transformation into a ceramic may be carried out.

With it, the glass composition may be used in a versatile manner, such as in cosmetic products (i.a. “anti-aging” products), medical products, edibles and animal food, paints and lacquers, and in polymers.

In this case on the one hand, the employment of the materials described herein may occur for protecting the product itself, but on the other hand also for achieving an antioxidative effect towards outside (e.g. in food additives).

BACKGROUND OF THE INVENTION

While the use of antimicrobially and/or biocidally acting glasses is known from a plurality of documents, the employment of glass compositions to stop or retard an oxidation reaction has completely been unknown so far.

By the use of antioxidants; oxidation reactions which have a negative effect on various products may be stopped retarded; or respectively.

Thus, for example, the presence of free radicals in the above mentioned products may result in undesired decomposition, discoloration or even in the complete uselessness of the product.

Thus the antioxidants may also have product preservative or even product maintaining properties.

Oxidation effects i.a. are also responsible for the aging of the skin. These oxidations, respectively the formation of radicals are caused i.a. by UV radiation of the sun light also by pollutants in the air, and respectively. These effects are i.a. also responsible for the formation of wrinkles. Items antioxidants are also utilized in cosmetic products which should take precautions against a premature aging of the skin (so-called anti wrinkle agents).

The antioxidants described and known so far are almost exclusively organic compounds. Vitamin C (ascorbic acid) and also vitamin E inter alia are well known to a person skilled in the art. Partly these compounds have the disadvantage not to be photo resistant by itself, i.e. that they may act as a free-radical generator. The known oxidant vitamin C i.a. suffers from this disadvantage, in particular when applied in small concentrations.

Thus there is a need for providing an antioxidant which may be used for the above mentioned applications and which doesn't suffer from the disadvantages of the known antioxidants.

SUMMARY OF THE INVENTION

It was surprisingly now found that glass compositions as defined in the claims may be used for the purpose of avoiding oxidation reactions, i.e. as antioxidant. The glass compositions may be oxidic.

The antioxidative compositions of the present invention have a high photo and temperature stability. Preferably the antioxidative glass compositions have a biocidal effect on bacteria, fungi and viruses or they are biostatic. Further preferably in contact with humans they are non-irritant to skin and even edible, in addition toxicologically harmless and environmentally compatible. Thus the compositions are preferably free of heavy metals, in particular when they are in direct contact with living beings.

The glass compositions used in this case comprise glass ceramics, fibers, granules, spheres and glass powders. A glass powder may be a powder that contains a plurality of glass particles in any form (also fibers), for example glass spheres having a particle size (d50) of smaller than 1 mm up to smaller than 500 μm, more preferably <100 μm and <20 μm, in particular <10 μm and <5 μm, or glass fibers having a diameter of smaller than 1 mm up to smaller than 500 μm, more preferably <100 μm and <20 μm, in particular <10 μm and <5 μm.

Glass ceramics according to the present invention may be prepared by annealing and may have different degrees of crystallinity.

The antioxidative effect may be based on a reaction of the glass with surrounding substances.

Reactions on the glass surface may also contribute to the antioxidative effect. Presumably the compositions produce the antioxidative effect in different manners, for example by the interception of free radicals, but also by the discontinuation of reaction chains which are responsible for the formation of free radicals and/or oxidation reactions and/or the exertion of an effect of chelation.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION

According to the following embodiment examples which serve for illustration the invention will be described in more detail:

EXAMPLE 1

Glasses were smelted from the raw materials shown in table 1 which afterwards were formed into ribbons.

By means of dry milling these ribbons were further processed into powder having a particle size of d50=4 μm. TABLE 1 Compositions (Synthesis Values) [in Percent by Weight] of the Glass Compositions according to the Present Invention Emb. 1 Emb. 2 Emb. 3 SiO₂ 71.2 45 Al₂O₃ 0.35 6.2 B₂O₃ P₂O₅ 6 66.3 Li₂O Na₂O 14.2 24.5 12.5 K₂O 0.05 MgO 4.2 CaO 9.9 24.5 7.5 ZnO 7.5 Fe₂O₃ 0.1 Emb. Emb. Emb. Emb. Emb. Emb. Emb. Emb. Emb. Emb. Emb. Emb. 4 5 6 7 8 9 10 11 12 13 14 15 SiO₂ 44.00 44.90 63.55 63.40 63.40 Li₂O — — Na₂O 11.90 11.90 14.60 24.50 24.50 14.60 6.57 6.70 5.80 — — 12.50 K₂O — — CaO 3.30 24.50 24.50 3.30 11.90 11.90 7.50 P₂O₅ 66.90 65.90 33.45 6.00 6.00 33.45 65.90 65.90 66.20 B₂O₃ 29.87 29.80 29.80 Al₂O₃ 6.20 6.20 6.20 6.20 6.20 SO₃ 15.08 15.08 Ag₂O 1.00 1.00 0.10 1.00 0.10 1.00 1.00 0.10 TiO₂ ZnO 15.00 15.00 33.56 32.56 16.00 15.00 7.50

The antioxidative efficiency has been detected by means of the so-called “Deoxyribose-Test”

-   -   (“The Deoxyribose Method”, Analytical Biochemistry, 165,         215-219, 1987).

The following diagram shows the hydroxyl radical inhibiting effect of embodiment 3 in dependence on the concentration:

Diagram 1 shows that embodiment 3 produces a clear hydroxyl radical inhibiting effect which increases with rising concentration.

It is possible to show that the antioxidative effect may be based on a discontinuation of the redox reaction chain. In the test method described herein the effect is based on a chelate formation (complexation) of iron which is required for the formation reaction of the free radicals. Thus the Fe⁽²⁺⁾/Fe⁽³⁺⁾ redox reaction will be discontinued.

EXAMPLE 2

An alternative test method for detecting the antioxidative effect may be carried out by means of the so-called “Protein-Carbonyl-Assay-Test” which is described in “R. L. Levine et al., Meth. Enzymol. 186, 464-478,1990”.

Diagram 3 shows the measure of the antioxidative effect on the basis of obtained and oxidized proteins. The test was carried out, before the irradiation with UV light (−UV) and after the action of UV light (+UV).

The lower the bar in diagram 3, the higher the antioxidative effect for the composition in each case.

The bar diagram shows that with embodiment 2 only few oxidized proteins were obtained, i.e. that the antioxidative effect was high.

Embodiment 3 also shows a clear antioxidative effect after UV irradiation.

EXAMPLE 3

Deoxyribose-Test for the Determination of the Antioxidative Effect of Shampoos which contain Glass Compositions according to the Present Invention. TABLE 2 Measured Optical Densities and Inhibition calculated thereof Optical Optical Density Sample/ Density at 352 nm, at 352 nm, 10% Concentration 1% of the Shampoo % Inhibition of the Shampoo % Inhibition Shampoo 1 0.3505 Not 0.2922 15.5 with 5% determinable glass composition (emb. 2) Shampoo 2 0.2426 29.9 0.2477 28.4 with 5% glass composition (emb. 3) Shampoo 3 0.3808 Not 0.3166  8.5 no determinable glass composition (support) Catalase 0.0471 86.4 Not Not (positive control) applicable applicable Reference 0.3459 Not Not Not (negative control) applicable applicable applicable

From the above table it will be appreciated that the shampoo which contains the glass composition according to embodiment 2 shows a light antioxidative effect when the test concentration of the tested shampoo is 10%.

In the test performed for the shampoo which contains the glass composition according to embodiment 3 a degradation of deoxyribose through hydroxyl radicals in an amount of about 30% can be determined, which corresponds to a distinct antioxidative effect.

The support itself (shampoo 3, without glass composition) shows with an inhibition of 8.5% a light antioxidative effect.

The shampoos 1 to 3 have the following composition (table 3): Shampoo 2 Shampoo 1 Shampoo 3 (Support) [percent by [percent by [percent by No. Raw Material INCI* weight] weight] weight] 1 Texapon NSO Sodium laureth 50.00 50.00 50.00 sulphate 2 Amphotensid B4 Cocamidopropyl 8.0 8.0 8.0 betain 3 Water, Water 33.29 38.29 33.29 demineralized 4 Euxyl K4O() Methyldibromo- 0.1 0.1 0.1 glutaronitril and phenoxyethanol 5 Edeta BD Disodium 0.1 0.1 0.1 EDTA 6 Veegum Ultra Magnesium 2.0 2.0 2.0 aluminium silicate 7 Propylene Propylene 0.01 0.01 0.01 carbonate carbonate 8 Glass composition 5.0 — — according to emb. 2 9 Glass composition — — 5.0 according to emb. 3 10 NaCl Sodium chloride 1.5 1.5 1.5 100.00 100.00 100.00 pH value 10.2 5.7 5.1 *international nomenclature of cosmetic ingredients

EXAMPLE 4

Deoxyribose-Test for the Determination of the Antioxidative Effect of OW Formulations, which contain Glass Compositions according to the Present Invention. TABLE 4 Measured Optical Densities and Inhibition calculated thereof Optical Density at Optical Density at 352 nm, 1% 352 nm, 10% Sample/ of the OW of the OW Concentration Formulation % Inhibition Formulation % Inhibition OW formulation 1 0.3986 Not 0.3798  4.1 with determinable glass composition (emb. 2) OW formulation 2 0.2505 36.8 0.2039 48.5 with glass composition (emb. 3) Catalase 0.0829 79.1 Not Not (positive control) applicable applicable Reference 0.3962 Not Not Not (negative control) applicable applicable applicable

From the above table it will be appreciated that the OW formulation which contains the glass composition according to embodiment 2 shows a light antioxidative effect if the test concentration of the tested formulation is 10%.

In the test performed for the OW formulation which contains the glass composition according to embodiment 3 a degradation of deoxyribose through hydroxyl radicals in amounts of about 37% respectively 49% can be determined, which correspond to a distinct antioxidative effect.

The OW formulations 1 and 2 have the following compositions (table 5): OW Formulation 1 OW Formulation 2 No. Raw Material [percent by weight] [percent by weight] 1 Alacel 165 V 6.65 6.65 2 Cetyl alcohol 0.95 0.95 (Lanette 16) 3 Stearingsaure L2 4.75 4.75 SM (GV S052) 4 Neutral oil vegetab./ 22.8 22.8 Crodamol GTCC (GV N020) 5 Demineralized 59.85 59.85 water 6 Glass composition 5.0 — according to emb. 2 7 Glass composition — 5.0 according to emb. 3

Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.

In the foregoing and in the examples, all temperatures are set forth uncorrected in degrees Celsius and, all parts and percentages are by weight, unless otherwise indicated.

The entire disclosure of all applications, patents and publications, cited herein and of corresponding German application No. 10332011.3, filed Jul. 14, 2003 is incorporated by reference herein.

The preceding examples can be repeated with similar success by substituting the generically or specifically described reactants and/or operating conditions of this invention for those used in the preceding examples.

From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. 

1. A use of a glass composition for achieving an antioxidative effect.
 2. The use according to claim 1, wherein said glass composition is oxidic.
 3. The use according to claim 1, wherein said glass composition has a high photo and temperature stability.
 4. The use according to claim 1, wherein said glass composition comprises the following ingredients SiO₂ 0-80 percent by weight P₂O₅ 0-80 percent by weight SO₃ 0-40 percent by weight B₂O₃ 0-80 percent by weight Al₂O₃ 0-20 percent by weight Li₂O 0-30 percent by weight Na₂O 0-40 percent by weight K₂O 0-30 percent by weight CaO 0-25 percent by weight MgO 0-15 percent by weight SrO 0-15 percent by weight BaO 0-15 percent by weight ZnO 0-40 percent by weight Ag₂O 0-5 percent by weight F 0-10 percent by weight J 0-10 percent by weight Fe₂O₃ 0-5 percent by weight and optionally trace elements and/or conventional refining agents in usual amounts, wherein the sum of SiO₂+P₂O₅+SO₃+B₂O₃+Al₂O₃ is greater than 20 percent by weight and up to 80 percent by weight.
 5. The use according to claim 1, wherein said glass composition is free of alkali oxides.
 6. The use according to claim 4, wherein in said glass composition the sum of CaO+MgO+SrO+BaO+ZnO is from 5 to 50 percent by weight.
 7. The use according to claim 4, wherein in said glass composition the sum of Li₂O+Na₂O+K₂O is from 5 to 60 percent by weight.
 8. The use according claim 1, wherein said glass composition comprises the following ingredients P₂O₅ 1-15 percent by weight B₂O₃ 0-5 percent by weight Al₂O₃ 0-10 percent by weight Li₂O 0-15 percent by weight Na₂O 5-40 percent by weight K₂O 0-25 percent by weight CaO 5-40 percent by weight MgO 0-15 percent by weight SrO 0-15 percent by weight BaO 0-15 percent by weight ZnO 0-40 percent by weight Ag₂O 0-5 percent by weight J 0-10 percent by weight Fe₂O₃ 0-5 percent by weight.
 9. The use according to claim 1, wherein said glass composition comprises the following ingredients SiO₂ 0-10 percent by weight P₂O₅ 25-75 percent by weight SO₃ 0-30 percent by weight B₂O₃ 0-40 percent by weight Al₂O₃ 0-10 percent by weight Li₂O 0-15 percent by weight Na₂O 0-40 percent by weight K₂O 0-25 percent by weight CaO 0-40 percent by weight MgO 0-15 percent by weight SrO 0-15 percent by weight BaO 0-15 percent by weight ZnO 0-40 percent by weight Ag₂O 0-5 percent by weight J 0-10 percent by weight Fe₂O₃ 0-5 percent by weight.
 10. The use according to claim 1, wherein in said glass composition the sum of CaO+MgO+SrO+BaO+ZnO is 0 to 40 percent by weight.
 11. The use according to claim 9, wherein said glass composition is free of alkali.
 12. The use according to claim 9, wherein in said glass composition the sum of Li₂O+Na₂O+K₂O is 5 to 50 percent by weight.
 13. The use according to claim 1 in cosmetic products.
 14. The use according to claim 1 in deodorizing products.
 15. The use according to claim 1 one of the fields selected from oral hygiene, dental care, oral care, gums hygiene.
 16. The use according to claim 1, which should take precautions against a premature aging of the skin (“anti aging” creams respectively anti wrinkle creams).
 17. The use according to claim 1 in medical products.
 18. The use according to claim 1 in edibles.
 19. The use according to claim 1 in animal food.
 20. The use according to claim 1 in paints or lacquers.
 21. The use according to claim 1 in one selected from the group of plasters, cements and concrete.
 22. The use according to claim 1 in antifouling products.
 23. The use according to claim 1 in polymers. 